Photographic films

ABSTRACT

Anti-static photographic films comprise a self-supporting synthetic plastics film base, such as a polyethylene terephthalate film, having superimposed on at least one side a gelatin-containing subbing layer and a radiation-sensitive layer superimposed on the gelatin layer, in which an anti-static material is included in the gelatin-containing subbing layer or being interposed as a layer between the gelatin-containing subbing layer and the radiation-sensitive layer, said anti-static material comprising a polymer or copolymer containing repeating units of the formula: ##STR1## wherein R represents hydrogen or methyl, R 1  represents methyl or ethyl, R 2  and R 3  each independently represent methyl or ethyl or R 2  and R 3  taken together represent --CH 2  CH 2  OCH 2  CH 2  -- or --(CH 2 ) n  -- where n represents 4, 5 or 6, A represents an alkylene or substituted alkylene group and X -  represents a chloride or acetate ion, said polymer or copolymer having an average molecular weight in the range 5,000 to 2,000,000. Preferred anti-static materials include a copolymer of equimolar amounts of trimethyl-β-methacryloyloxyethyl ammonium chloride and styrene; a copolymer of equimolar amounts of ethyldimethyl-β-methacryloyloxyethyl ammonium bromide and methyl methacrylate; a copolymer formed from equimolar amounts of trimethyl-β-methacryloyloxyethyl ammonium acetate and styrene; a copolymer formed from 15 mole % trimethyl-β-methacryloyloxyethyl ammonium chloride and 85 mole % styrene; a copolymer formed from 50 mole % ethyldimethyl-β-methacryloyloxyethyl ammonium bromide and 50 mole % methyl methacrylate and a homopolymer of trimethyl-β-methacryloyloxyethyl ammonium chloride.



